Wax-thread sewing-machine.



H. P. SCHOENKY. wAx THREAD SEWING/MACHINE. APPLICATION FILED IANJU. |916- Patented Oct. 9,1917.

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245252655@ f .KW 7%735 H. P. SCHOENKY. wAx THREAD sewme MAcmNE. APPLlCATlDH FILED IAN.10. \9\6.

Patented Oct. 9,1917.

H. P. SCHOENKY.

WAXTHREAO SEWING MACWNE. APPLICATION man 1AN.10.\9\6.

H. P. SCHOENKY.

WAX HREAD SEWlNG MACHINE. APPLlcMloN m50 1m10.191s.

1 ,242,606. Patented Ot. 9, 1917.

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wAx THREAD sEwlN MACHINE.

APPLICATION FILED JAN.10. |916. 1,242,606. Patented oct. 9,1917.

` 8 SHEETS-SHEL 6.

H. Pi SCHOENKY. wAx THREAD SEWING MACHINE.

1,242,606. APPLICATION FILED IAN. IO, 1915. 9 8 SHEETS-SHEET I.

I@ Il! IIE i f wie! gli H. P. SCHOENKY.

WAX THREAD SEWING MACHINE. APPucATlon FILED 1AN.10.19\6

1,242,606. Patented oet. 9,1917.

8 SHEETS-SHEET H.

Zzeefez' are/Zri' @Wr/MMM@ 7 la Va `eitizenfo the UnitedStates, and a resi-V masticar; assrenona 'ii-'Manteau siren on ST. LOUIS, MISSOURI, A- oonlonnrrmn HENRY. 12. SGHDENEY, or str. Leurs,

MAGHINEBY e Toorn ooMrANY,

or MISSOURI. Y Y. ,i

WAX-'marian SEWING-MACHINE.

Specification of Letters Patent.

1,242,606. Patented Oct. 9, 191 '7.

Applictbnfiled'anuary 10, 1916. Serial No. 71,179.

machine on v`the line 5 5V in Fig. 3, looking atV it Vfronti the front;

Figo is a hori'zronltalsectionthrough the machine` on tiie line 6;-6: in Fig. 3, looking down, showing the 'Work table andj feeding To 'ail'whom it may concern: i

Be it knovvf'ri that I, Henri' P S'ononn KY..

dent of the cit/'y ofA St. Louisi and State ofY Missouri, have invented a new and useful Improvement in VWfaiel"hread Sewing-Machilies, of which the following is a spec-itiv cation. Y

This invention relates to leather sewingV machines of the lock stitch type, and is in tended particularl)r for use inrshoe lrepair shops for sewing on outsoles, 'but the inven' tion isY not restricted to such stitching ma chinos. Y

The objects of the invention are simplicity.

ofi construction, strength and durability, together with ease of operation and adjustment for all classes of Worin, suclras to make a practical stitching machine Jfor use by ordinary shoe Workers Without the attention of skilled operators'or machinists. Further objects of the invention appear hereinafter.

The invention consists in the iiormand ini the arrangement of the various partsot th machine so as to produce a uniform stitch regardless of irregularities inft'hef 'thickness or character of the Work.` The inventioni further consists in the arrangement of the parts for convenient operation of the inaehine, and for easy inspection and' adjustment or repair, as hereinafter described'.- What; the invention consists infis further'se forth* in the appended claims.I Y

A machine embodying the invention in an operative form is shown in the accompany-` ing drawingshforming part ofV lthis specification. The same reference charactersvare used throughout the severaf Views of the drawings to designate the same parts of the' machine.

Referring to the drawings, Y

Figure 1 is a front elevation of a :machine embodying the invention;

Fig. 2 is a side View of the right :hand side' of the machine, theV driving 'Wheell and 'aj part ot? the fra-me being removed to d iiscfose the operating parts;' Y A Fig. 3 is a side view of the'ifeft handg side of the machine. the frame being partly removed; l

Fig. 4 is a rear elevation of the machine g:

Fig. 5 is a vertical Section through the mechanisinland looper actuating mechanism in plan;v

Fig. 7 is a vertical section through a portion of the machine on the line 7-7 in Fig. 6, looking in the direction of the arrows;

Figs.A 8 and 9 are a plan View and a front View, Yrespectit'ey'7 of the stitch-forming mechanism in the operation Yof forming a stitch, the Work heingre'moved and the work table being hrolnnV away in the plan View to disclose the parts beneath, showing the position of the parts at the beginning of the formation of the loop in the needle thread, the main cam having rotated through 230 from its zero position;

Figs. 10 and 11 are similar views to Figs.

8 and 9 showing the parts after the looperV haspul ed the loopopen Vand the shuttle has ick'ed it up, the main cam having rotate throu ghV 275.

Figs. 12 and 13 are similar views, showing the parts after the looper has cast off the loop and the shuttle has oscillated far enough to carry the loop around the hobbin thread, the main cam having rotated through 305 Figs, 14 andrl') are similar views, showing the parts after the shuttle has completed its loop arryingmovement and'has cast oif theV loop,V and after the take-up has started to pull the stitch tight, the main cam hav rotated through V330D Figs. 16 to 18, inclusive. are detail views of the awl holder and channeling knife, Fig. 16 being a front view. and Fig. 17 beinizr a vertical section and Fig. 18 a horizontal section on the axis of the holder:

Fig. 19 is a detailf View of the holdingr bolt Jfor the awl removed from the other parts;

Fig. 20 is a sectional view oit' two pieces of leather seatedI together1 showingl the'stitch formed by the machine: and

Fig. Q1 is a diagram illustrating the sequence of operation of the various parts ot the machine, and the time intervals, hetween the various movements,

Gc'ncml description cf the machine.

The machine shown in the drawings has a main frame consisting of a base 10, side walls 11 and a front Wall 12. Projecting forward from the front Wall is a table 1.3 for supporting the Work being sewed, and an arm 14 for supporting the presser foot and needle bar. The front end of the arm 14 is covered by a plate -15 which is provided with a chumber for heating it by steam. A steam chamber 16 surrounds the recess 17 below the work table for the shuttle and bobbin. Steam is circulated through the steam chambers by means of pipes 18. The work table has a slot 19 through it parallel to its front edge for the aWl and needle to Work through. The work is held by the operator With its top side up, and is guided by hand. The Work is fed forward for each stitch by the aWl 20, which operates from below the work table in front of the shuttle. The awl is carried by a vertically and sidevvise movable holder 21, which also carries a channel cutter 2) for grooving the underside of the Work to form a channel for the thread. The work is held in place on the table by a presser foot 32 which operates from above the table.

There are two threads used in forming the stitch, the top thread 40 being led through the eye of the needle 41 which operates from above the work, and the bottom thread 50 being supplied from a bobbin 51 which is carried by the shuttle 52 which operates belovv the Work table. The stitch forming mechanism comprises also a looper 60, which operates below the table in connection With the shuttle, and a take-up lever which cooperates with the needle for measuring the length of top thread required for each stitch, and for pulling both threads tight at the completion of the stitch. The top thread is locked by a thread clamp 75, which is released during the thread measuring movement of the take-up lever. The needle and awl are both straight, but the invention is not restricted to a straight needle and a straight avvl.

The awl, feeding mechanism, presser foot, needle, shuttle, looper, take-up device and thread lock are all operated from a rotating cam disk S0 mounted on the main shaft 8l of the machine. The main shaft 81 is horizontally journaled in bearings 82 in the side Walls 11 of the machine frame, and has a hand wheel 83 on its right hand end. The main shaft is driven from a suitable source of power, such as a foot pedal and crank or a small electric motor, by means of a belt running in a groove 8-1 in the hand wheel.

A WaX pot 66 is provided for waxing the thread. The Wax pot is located on top of the frame of the machine at the back, and is steam j acketed for keeping it hot. The thread is led to the wax pot from any suit- Vbolt goes, through a able source of supply, such as a spool not shown in the drawings.

AwZ and channel cutter.

The awl 20 is adjustably secured to the awl holder 21'by means `cfa-clamping bolt 201 whichY has a hole through'it under its head for the avvl,V and a pin 202 on the inner side of the head in line with the hole for the end of the aWl to rest on. The' clamping transverse hole 203 through the upper end of the awl holder from back to front, and has a square shoulder 20a on the inner side `of its head which engages in a Vhorizontal groove 205 on the back side of the holder. The hole 203 is slot shaped, with its long axis vertical, and an eccentric 206 is arranged on the clamping bolt partly in the slotted hole, the diameter of the eccentric portion just filling the Width of the hole. The eccentric has a Hange which bears against the front of the awl holder around the hole. By rotating the eccentric, the clamping bolt is adjusted horizontally toward one'side or the other of the machine. The awl, clamping bolt and eccentric are secured in adjusted position by screwing up the nut`207 on the front end of the clamping` bolt.

he channel cutter 22 comprises a plate carrying a pair of knives or chisels 221 which are arranged one on each side of the avvl. The upper edges of the knives cut into the under side of the Work at the top of the upward movement of the aWl holder, thereby forming a shallow groove connecting the aWl holes on the under side of the Work. The slot 19 in the Work table is long enough to permit the channeling knives to operate through it. The channel cutter 22 rests on the top of the awl holder and has a flange 222 which hangs over the front edge of the aWl holder and is clamped to the eccentric and aWl holder by the clamping nut 207. Hence, the channel cutter is adjustable with the awl lengthwise on the awl holder.

Atal-feeding mechanism.

The awl holder 21 is mounted to slide horizontally from side to side in a slide box 23, which 1n turn is slidably arranged for movement up and down in Ways 231 on a forwardly projecting portion of the front Wall 12 of the machine frame below and to the side of the Work table 13. The Ways are provided with gibs*l 234 Which'can be adjusted to take up Wear in the side box and Ways by means of screws 235. The slide bex has a horizontal slot in its front side for the awl holder to slide in, and this slot is covered by a removable front plate. The slot has a gib 232 which may be adjusted by screws 233 to take up Wear in the slide 2l and Walls of the slot.

holder may {il}V iitlerjn .veniently remoed IHS ,thecenter of the groove Yroth a groove Qlrnjs front .ing the axis of Vai ,oscillation of the @has a slot through Vit Vfront of the groove end 'of VVou 1t which engages in the awl holder.

and Y shifted Vsidevvise A far 1 end to which noethe caml disk to cause The avvl holder 21 extends through the slide box Qlland has a vertical groove E210 on theinner side oi its projecting end. This grooved end of the avvl holder slides in Jfront of the end of anoscillating shaft 24, and when the aWl is in alinement with the needle 210 intersects the VThis oscillaton its Iiront end Y Y A Y face intersectesghaft. Y YThis groove 241 axis yofthe oscillating shaft. in shaft 24 has a sector Q40 ,stands vertically in one extreme position of shaft Qdianld it makes an angle of Vabout forty-five degrees with the vertical in its other extreme position. An adjusting arm 25 is pivoted eccentricalli7 to the Jfront of the sector Q40, and maybe clamped in angularly adjusted position on said sector 'by the thumb nut 5250 and J- clamp bolt 251 which engages under the outer edge ofthe sector. The adjusting Varm extending crosswise in 241 on the sector. and a stud 252 is mounted in the slot in the :id justing arm with its inner end proieeting into the sector groove and fitted to slide therein toward or awayfrom the axis o the oscillating shaft 24 when the adjusting arm Yis angularly adjusted Qn the sector.

*.The *studE has a shoulder against which the :inner:

Y face of the adjusting ,arm heerst() clamp the ystud in the groove.v The `outer the stud 252 has -aroller Asecured groovefllg in the The sector Q husa scale marked Yon its outer edge for setting the adjusting arm 25 to position the Atud in the groove 241 at the proper' distance from the axis of the oscillating shaft 2l for sliding the aWl holder Whatever distance is desired for the length of the stitch.

f The oscillating shatVZl is movable ari-ally in Vits hearings towardtheY nach of the .machine to Withdraw the sector, stud and roller from the groove 210 1in theawl holder. VA springrrQflQhnorInally Qholds the sha Et and arts carried thereb`y`in forward position. the sector 2&0 back, the awl be freed `from the roller 254.

i enough to carry the avvl vendavvayn. from in ront'of the shut order that. 'the' `boletn, metY .bev-

' and r'eplacedVVA oscillating shaft one end of conneti'ng'l'od 26 is pivoted. VThe other end of the connecting rod is pivoted to thelovver end of an oscillating lever 2T which is piv'otallyniounted at its middle on a bearing on the hack of the fron Wall of the iframe." The pivotal 4axis. of the lever Q7 is parallel to that of the oscillating shaft S24. The upper end of the lever 27 carries a cam roll 270 which engages in a cam groove 28 onthe periphery the Vlever 27 and a roller :QQjvvhi'ch cooperates with a camV groove 31 inthe 'face'of 'the cam 870 to svving thebell crank lever andV raise and lovver the slide box for the avvl holder, and to hold it motionless in either position. V'Elhershape of the cam groove 3l is such that the avvl is raised to penetrate the Work, is held up until the feeding device has moved the awl into vertical ahnement with the needle, and is withdrawn in advance of the downward movement of the needle.

Presser `foot mechanism.

The presser foot 32 is mounted Von the lower end of a square slide'bar 33 which 1s guided for up and down movement in a suitable slot in the front of the arm 14 behind the steam chamber plate l5. The toe of the presser foot rests upon the work over the'ivorli` table, and is provided with a slot Y 34: through it in vertical Valinement with the 19inV the vvorletable The presser foot is held dovvn by' aclamp bar ivhich cooperates'ivith aidant o rated rocker arm or leveril. Thefelanip y)ar has v:Csquare'ihole in it near its front end through which the squareV slide bar passes loosely. he clamp bar is supported at its Jfront end b v means oi' a spring Bill which' is mounted on n rod which projects down from a lug ll) on the under side of the front plate l5 onY the arm 11i of the machine. The rod 2523*). passes loosely;through a hole in thovfront endrof the clamp bar yand carries a 'stop 333 above the4 eind.` of fthe lampV bar against which *the latter is pressed hold it horizontal and free of the slide bar when the clamping lever is not held down at Vits back end b v the rocker arm or lever 36.

The rocker lever 36 is pivoted at its hind the presser foot slide bar. roller SG1 of .the rocker lever bears by the spring to o `baclfevndi of the clamp bar', and the the rocker lever h asa Vr( ller l 1L gethe peripicry of ilo ico

notch 37 in the edge of the cam disk; and a second short notch 38 permits the release of the clamp at the end of the stitch for the purpose of shifting the work if desired.

A hand lever 39 for lifting the presser foot by hand is pivoted to a lug 150 on the t'ront plate 15 of the arm 14, which projects down alongside of the slide bar 33 above the clamp bar. The hand lever has an arm 390 which is provided with a cam slot 391 in which a pin 392 on the slide bar works. A light spring 393 holds the hand lever and presser foot down. The hand lever can be operated conveniently only when the roller 362 is in one of the cam notches 37 or 38, although the front end or the clamp bar may be depressed by means of a suitable tool to release the slide bar regardless of the position of the cam.

Needle and shuttle actua/.ting mechanism.

The needle 41 is clamped to a block 42 upon the lower end of the needle bar 43 by means of a clamping nut 421 which screws on a stud 422 in the front of the block 42. The shank end of the needle goes through a hole in the clamping stud and bears against a pin which is fixed in the clamping block, and a washer 423 is arranged on the stud between the clamping nut and the needle to hold the latter in place. The needle bar 43 slides vertically up and down in a suitable slot in the arm 14 of the machine behind the front plate 15. An adjustable gib 44 is provided for taking up wear in the needle bar and guide slot.

The needle bar is raised and lowered at the proper times for making the stitch by means of a series of links and swinging arms and levers actuated from the main cam 80. A link 45 is connected at one end to the needle bar and at the other end to the front end of a horizontal rocker arm 46 which is pivoted near its middle on the shaft 73 to oscillate in a vertical plane. The back end of the rocker arm is connected bv means of a link 47 to a swinging lever 48 Y which is pivoted at one end to the back of the frame of the machine. The swinging lever carries a cam roll 481 which coperates with the cam groove 49 in the face of the cam.

The lower thread 50 is wound on a bobbin or spool 51 which is carried by a stationary bobbii case 53 mounted loosely in the shuttle 52. An arm 54 pivoted on the front of the frame under the work table a stud 531 on the bobbin case to hold it stationary. This arm can be thrown out of the way when it is desired to remove the bobbin. The shuttle 52 is loosely mounted in an annular recess 171 in the frame under the work table, and is held in place by means of a removable ring 172. The shuttle is oscillated by means of a driver arm 55 which loosely engages a notch in its periphery in front of the point of the shuttle. The driver arm 55 is fixed on the front end of the horizontal shaft 56 which is journaled in the frame under the Work table and which has a spur gear 57 upon its back end engaging with a rack upon a vertical sliding bar 58 which is mounted in a vertical guide slot in the frame back of its front wall. The rack bar is connected by means of a link 59 with the front end of the swinging lever 48 which operates the needle bar. Upward movement of the front end of the swinging lever 48 causes the needle bar to lower and simultaneously oscillates the shuttle in the same direction as the hands of a clock, and vice versa.

Looper mechanism;

The looper G0 slides Jforward and back in a recess below the work table, its path of movement passing close to the left side of the path of movement of the needle. looper is attached to a horizontal rod 61 which is slidably arranged in the frame below the table. The looper rod is operated from the cam disk 80 by means of a link 62 whichfconnects its back end with the upper end o n This swinging lever 63 carries a cam roll 631 which engages with a cam groove 64 in the face of the camV disk cause the loo er to move forward Vto pass the needle after the latter has penetrated the work, and to withdraw it immediately. The front end of the looper is provided with a hook which catches the needle thread and pulls it back in the form of a loop into the recess under the work table and in front of the point or hook on the periphery of the shuttle 42. after the shuttle starts to roengage its hook from the loop of needle thread, and the shuttle hook carries the 'Wam pot and thread guides.

` et ge ofV theV Wax peti s 52 havingvcenter holes tor the thread are sqneez'edbetvveen the guides and bottoms ofthe openings in the Walls to strip the Wax from the thread. A loop ot' the needleV thread is passed hack Vfrom the top roller 6T around a roller 69 von the end oi the taleup" :lever V7CV7 :the thread passing forward from theroller 69 to th floyvertix'ed .roller 67 1uponthe frontier jnaehine. From the lower roller the threadle'ds aorossth'e heated front plate 15 otffhe arm and under alight spring GS at the lower edge of the arm.

oke-W1 mechanism.

rhe take-up lever T0 is pivoted upon the arm 14 back` ot the guides for the presser foot and needle bar, andis operated from the disk 80. Vconneeti'ng link 71 is pivotedatone endto the'taike-n lever and atthe otherzendgto' the irontj en of a crank lever T2' haviAk twog leveri arms "securely lteyed on a horizontal shaft 73. The rear armV T21 of theeranklever carries a cam roll 722' at its end which engages in a groove 74 on the'face ofthe earn disk 80. The shaft ''lylthus'forms a portion of the crank lever''Q. ,and isjournaled at, its ends in fixed bearings i'r'ifthe frame Voiftlie machine. The middle portion of the shaftg supports the roelterfarm 36 forelanpipgthe presser foot7 and "this Vshat't alsojsnpports the lever 46 which operates' the needle har.

A'thread clamp 75 is provided upon the beek ofthe machine for clamping the thread beforeV it enters the wax pot. The thread clamp] onsists o a vertically movable clampingA pin carrying a disk T51 at its lip'vverV end Whichelamps the thread against t eloivertaee ,of the lug To on the lower 4 l Theclamping disl'i's held lightly against the thread at all times by nieai's df' aspr'i'rrrg'q? Whieh rests upon the lufr 'T6 1 and,"oeans against an adjustable mitflo on VVtl're threaded stem of the thread Clamp 75. The Clamping disk is held in clamping position by meansl of the clamping lever 77 which is pivotally lmounted' at one end nbeneath the Wax potand which carries a'rolleri'l" V'at itsother end for' cooperating Withone ,edge portioniothe periphery of theE earnfdislr 80; 'The eelmping :lever has ajstateitnamgsergw "772 which 'is adapiedto firear-"against the lower face of thelampihgdiskand pressit against the tlrregalol2 d tio` hymeansof al loelrnut 7?3. The earn dislli, twpipidtehes in its periphery, and vvh3 ithe' rollerl'l drops into one or the therof thesenotehes the pressure of the clamping lever against the clamping disk is relieved. (Dnelnoteh ffissnitahly located upon ther-iam Vdiskto open the thread look Whielif the* 'take-up. lever is measuring thread.

" V'C9 `isf located upon the cam i Thef'screw is'held in adjusted posithe notch 3S which relieves the in line `with Y the presser foot upon eoinplep ressu re. on

Operation of the mee/lime.

ifig. 21 shows diagrannnatically the order in which the various parts of Vthe machine operate, and the'relative positions of the Working parts at every stage in the formation ot ar stitch. VBy turning the hand wheel 83 so as to hring the cam notches 38 and 79 under the rollers 362 and 771 on the levers 3h and 77 which operati` the presser tootclalnp and thread look. respectively. the presser toot. is released and the thread look is opened, and the work can be brought in position on the Work table under the presser foot, and a short length of thread pulled through the eye ofthe needle.

A slight movement of' the top of the hand Wheel away from the operator clamps the presser foot down on the Work and closes the thread look, and the machine is ready for operation by power. The Cani is rotated in the direction ot' the arrows in Figs. Q and Il, and the shapes ot the various emu grooves and shapes and arrangenu-nt of the levers and links are such as to produce synchronous movement of the operating parte as follows:

First, the awl moves up through the work, moves sidevvise toward the lett to feed the work under the needle, and then 'withdraws down through the work and moves hach toward the right to its initial position out ot the vvay of the needle. During the sidevvise movement ot' the a\vl to toed the ivorlr the presser foot is released.

VThe needle moves down simultaneously with the Withdrawal ot the awl, and carries the top thread through the work and below the path of movement of the looper. and as slightly to form a loop ot thread 'tor the looper to pass through. Thu-ing the downward movement of the needle the shuttle is turning in the same direction as the hands of a clock to bring its point in readiness to pick up the loop. E i n Y The needle''and'fshuttle rest while the looper is'eoinpl'eting its forward movement; and during the: latter partof Athe forward movement of the looper, the parts being in the positions shown in Figs. takeeup lever moves away from the front of the arin 1l to measure thread for the stitch,V the thread look being open during thisr movement. The resistance ot the thread to movement thrmlgh the thread elainp and WartV pot causes all the slack to he taken out of the thread and the loop around the looper .to be pulled tight. so that take-uppulls' a variablelengthof thread izo through the thread lock substantially equal to whatever length may be needed for the stitch. The length of thread between the thread clamp and needle is considerable and it will stretch more or less, depending on the tension o the spring (52, thereby diminishing or increasing the amount of thread pulled through the thread lock for a ce1'- tain length of stitch. Hence, the length of thread pulled through for the stitch can be slightly increased or diminished, by adjusting the tension of the thread clamp spring T52, and thereby the tightness of the needle thread and stitch can be regulated. For sewing thick leather the tension of the spring may be increased, and for thin leather it may be slackened.

Following the thread measuring movement, the thread lock closes and the takeup lever 70 moves forward to pay out thread. The looper 60 simultaneously moves back, pulling' a loop oi thread with it across the path of movement of the point of the shuttle 52. During the last portion of the backward movement of the looper the needle starts to rise, and the shuttle starts to rotate anti-clockwise, so that when the looper reaches its extreme rear position the shuttle point has fully entered the loop, shown in Figs. 10 and l1. The looper then moves forward a short distance to free its hook end, and the continuing rotation ot' the shuttle pulls the loop oli the looper and over the linger G5 and carries it down behind the bottom thread 50, as shown in Figs. l) and 13. The bottom thread is held in the stationary bobbin case 53, and is under tension, produced by a. spring in the bobbin case, to keep it taut. During this movement of the shuttle the take-up lever moves forward to pay out enough excess thread, which is pulled through the eye of the nee` die by the shuttle, to permit the loop to pass around the shuttle and bobbin case. The looper then goes hack to its rear position out of the way of the loop, and remains at rest during the remainder' of the stitch forming operation, and the shuttle continues its rotation in an anti-clockwise direction until it has nearly reached its starting point, as shown in Figs. ll and l5. During the last portion of the rotation ot' the shuttle the take-up lever moves back to talie up slack in the top thread 40 and pull the loop off the shuttle and around the bobbin through the space between the shuttle and driver arm 55.

The eii'ect of the arrangement of loopel and shuttle is to throw a twisted loop of the top thread around the bottom thread, as shown in Fig. 15. The take-up lever continues to pull in slack, until all the excess thread measured for the loop is taken up and the loop is pulled up into the work, carrying a bight of the bottom thread with it.

the loop from The act of pulling the top thread 'into' the needle hole untwists the loop and puts a twist in the bight of the bottom thread, completing the stitch, as shown in extent to which the bottom thread is pulled into the needle hole is determined by the tension on the top thread and consequent stretch in the top thread during the thread measuring operation.

Upon finishing the sewing, the hand wheel is turned to bring the notches 38 and 79 in the cam under the rollers which cooperate therewith, thereby releasing the presserA foot and opening the thread lock to permit the work to be removed from the work table.

From the foregoing description it is apparent that the stitch forming mechanism is adapted to operateupon work of dilerent character and thickness, and can be adjusted to form stitches of different length, as mayl be desired. The stitches are pulled uniformly tight regardless of their length and of the thickness of the work, and the tension may be adjusted to suit the character of the work. The presser foot positively clamps all thicknesses of Work with the same pressure without requiring any adjustment, and it and the thread lock are automatically released at the completion of the stitching operation to permit removing the work from the table. The bobbin is easily removed and replaced without readjusting any of the parts; and the length of stitch may be adljusted without readjusting the thread tension. The thread measuring device is simple and not subject to derangement; and there are no small parts exposed to possible injury except the needle and awl, which are readily replaced. The form of the stitch is well suited to sewing on soles, as the twisted bight of the bottom thread will continue to lock the top thread after the portion of the thread in the channel is worn through.

The invention is not restricted to the details of construction shown and described, as it is evident that they are susceptibleV of modification.

I claim the following as my invention:

1. A sewing machine comprising a needle and shuttle operating on opposite sides of the work, a stationary bobbin carried by the shuttle, a looper, a thread lock, a take-up device between the thread lock and looper, and means to operate the needle, shuttle, looper thread lock and take-up device to throw a. twisted loop of needle thread around the bobbin thread and pulling it ti ht to complete the stitch, whereby a twistedight of bobbin thread is pulled into the stitch to lock the needle thread. v A, Y

2. A sewing machine comprising a needle andV shuttle operating on opposite sides of the work, a stationary bobbin carried bythe shuttle, a looper, a thread lock, a takevlup device between the thread lock andlooper,

Fig. 20. The Y prising'a cam,

- more' anlfeyelpeiite @een operating table, a sliilttl and' means to ,operate theV needle, shuttle, looperY thread lock and take-up device to thron7 a'loop oneedle thread around behind thetbo'bbin thread ina direction.V opposite to that in which' the stitches are being formed, whereby a twisted bight of bobbin thread is pulled into the stitch to lock the needle thread.

BLA sewing machine comprising a Work table, a needle "bar'operating from one side of said ivorlr table, a shuttle operating on the opposite side of said Work table, a shaft for operating said :shuttle and arranged for oscillation therewith, means for operating said needle bar Vand shuttle in synchronism coma swinging lever cooperating with said cam to follow its movements, a rocker arm arranged to reciprocate said. ncedle bar, a link connection from said lever to said rocker arm, and a rack and pinion connection from said swinging lever to said oscillating shaft for oscillating said shuttle. 4. sewing'lmachine comprising a Work table, La needle har operating from one side of 'saiddwoi'k tahie; a A shuttle operating on the oppositel Vside ofV saidV Work table, a looper, means'for reciprocating said looper and for operating said needle bar and shuttle in: synohronisrn comprising a cam having two grooves, a rocker arm arranged to reciprocate said needle bar, a swinging lever cooperating with said cam to follow one of said grooves, a link connection from said lever to said rockerA arm,` an oscillating shaft arranged toosci'llatesaidshuttle, and a rack and'ipinionkcennection from said swinging lever to said' oscillating shaft, and a second lever cooperating with said cam -to follow the other groove, said second lever having a link connection with said looper.

5. A sewing machine comprising a Work table and an eye-pointed needle operating fromi'one side of said Work table, a shuttle and la looper operating nponY the opposite side ot saidfvvorkiabla-the Vpath ofmovei'nentfofi saidlooper `passing Vbetween the thread fand needle "when the needle is theVV worin' a V'hook f on said loper ada-gi df tospread"L open a loop of needle thread," a-fixed 'hook spaced Jfrom said work tainle in Vthe path of Vmovement ot said looper, and a hook onsaid shuttle adapted to piel;l np the loop on saidlooper hook and pull' it "iariid said fixed" hook.

G. A sewing machine comprising a Work from one side of said Work operating upon the opposite side of said work table, a iixed hook for holding the needle thread, said fixed hook being spaced from said Work table. and a. hook on said shuttle adapted to pick np a loop of needle thread. and pull it around said lixed hook, and a stationary bobbin holder carried by said shuttle, the movement of said shuttle around said holobin holder throwing said loop around the'hobbin thread. 'A

Arsevving machine comprising a work table and" an eye-pointed needleoperating from one sideof said work table, a shuttle operating npon tlicopposite side of said Work table, a fixedl hook for holding the needle thread, said fixed hook being spaced from said work table, and a hook on said shuttle adapted to piek up a loop of needle thread and pull it onto said fixed hook, and a stationary hobbin holder carried by said shuttle, the movement of said shuttle around said bobbinl holder Vtwisting said loop around the hobbin thread, and a takenp device for pulling in the needle thread to pick np a twisted bight of bobhin thread.

S. A lock st'tch sewing machine comprising a work table, a needle for carrying the top thread throno'hthe Work, a looper for picking up said thread on the opposite side of the Work to that on which the top thread lies and holding it momentariiy, means for holding the lower locking vthread for= passage of the needle thread loop around the same, anda taire-np device having lan'initial movement for pulling the loop tant against the looper While in the needle loop, said take-np device having a further movement `for pulling thread from the thread supply.

9; A lock stitch sewing machine compris ing a work table, a needle for carrying the top thread through the Work, a looper for picking np'said thread on the opposite side of the work to thatV on'which the top thread lies and holding it momentarily, means for holding the lower lockingwthread for passage of the needle'thread loop around the same, and a taire-up device having an initial movement for pulling the loop taut against the looper While in the needle loop, said take-np device having a further movement for pulling thread from the thread supply, and a thread lock between saidtakemp deviceA and thread supply. I

'10. A sewing machine comprising a Work table, needle `for' forming af loop of the top thread beneath the Work, alooper for pileing' up saidthread (inthe Vopposite side of the Work to that on ivl'iiehthe top thread lies, and a take-up device having an initial movement for pulling the Vloop tant against the looper While in:` the.Y needle loop, said talreenpVA device having a lfur-therV Vmovement for pulling thread from the` thread supply, and a threadloei hetiieesaiditairempl'de- YYrinzeiand thread supply, said thread lock being at a distance from the looper and having an adjustable tension device for maintaining a greater or less tension on said top thread during the movement of said takeup device for pulling thread from the snpp y.

11. A sewing machine having a needle for the top thread and a bobbin for the bottom thread, means for passing the bobbin through a loop of the .needle thread, a takeup device for the top thread for pulling the stitch tight, and a thread lock for holding the top thread between the supply@ and take-up, the take-up device operating to measure thread after the needle has carried a loop of thread through the Work, said take-up deviceV havin a fixed length of movement for measuring thread while the loop of thread is being held by the needle in the work at a fixed distance from the end of the stitch regardless of the length of stitch or thickness of the wor 12. A sewing machine havin a needle For the top thread and a bobbin tor the bottoni thread, means for passing the bobbin through a loopV of the needle thread, a takeup device for pulling the stitch tight, and a thread lock for holding the top thread between the supply and take-up device, the take-up device operating to measure thread after the needle has carried a loo of thread through the Work, said take-up evice having a fixed length of movement for measuring thread while the loop of thread is being held by the needle at a fixed distance from the end of the stitch regardless of the length of stitch or thickness of the work, and a tension adj ustment for said thread lock Wherehy the amount of thread measured by said take-up device may be regulated.

13. A sewing machine having a work table adapted to support the work right side up, an eye-pointed needle for the top thread arranged to operate from above said work table, a shuttle mechanism operating below the work table, and a take-up device operating on said top thread above the Work table for feeding the top thread and for setting the stitch, said take-up device operating while the needle is stationary at a fixed distance below the work table to pull a length of thread from the supply equal to that required for the stitch.

14. A sewing machine having a work table adapted to support the work rightsideup,an eye-pointed needle for the top thread arranged to operate from above said work ta ble, a' shuttle mechanism operating below the work table, and a take-up device operating on said top thread above the Work table for feeding the 1999 thread and for setting the stitch, said take-up device operating while Copies of this patent may be obtained for ve cents each, by addressing the were@ the needle isV stationary at a fixed distance below the work table to ull thread from the supply, and an adjustable tension device lfor maintaining a predetermined amount of tension in the top thread during the thread feeding operationv of the take-up device and for locking said thread during the stitch setting operation of said take-up device whereby the tightness of the top thread after the stitch is set is controlled.

l5. A lock stitch sewing machine having a work table adapted to support the work right side up, an eyefpointed needle for the top thread arranged to operate from above said work table, a looper mechanism operating below the Work table, means for holding the lower locking thread for passage ofthe needle thread loop around the same, and a take-up device operating on said top thread above the Work table for feeding the top thread, said talus-upV device having a fixed stroke and operating inV conjunction with the needle and looper mechanism While the thread is being held below thenwork thereby to pull the required length of thread from the supply irrespective of the length of the stitch and thickness of the Work.

16. A wax thread sewingmachine having a work table adapted to support the Work right side up, an eye-pointed needle for the top thread arranged to operate from above said work table, a looper mechanism operating below the Work table, means for holding the lower locking thread for passage of the needle thread loop around the same, and a take-up device operating on said top thread above the work table for feeding the top thread and for settin the stitch, said take-up device having a' 'xed stroke and operating in conjunction with the needle and looper mechanism while the thread is being held below the work thereby to pull the required length of thread from the supply, and an adjustable tension device for maintaining a predetermined amount of tension in the top thread during the thread feeding operation of the take-up device and for locking said thread during the stitch .setting operation of said take-up device wherebyT the tightness of the top thread is controlled.

Signed at St. Louis, Missouri, this eighth day of January, 1916.

HENRY P. SCHOENKY.

Commissioner oi' Patents,

Washington, D. G. 

